Bug#956612: libpango-1.0-0: broken kerning since 1.44

[Tomas Janousek]

Package: libpango-1.0-0
Version: 1.44.7-3
Severity: important
Tags: upstream

Since yesterday's apt full-upgrade of testing, font rendering in Gtk
applications is very bad, kerning is broken, text is wider than necessary,
it's very very unpleasant, I'd even say downright unuable without downgrading.

What I'm seeing is exactly this:
https://gitlab.gnome.org/GNOME/pango/issues/404#note_712911
https://gitlab.gnome.org/GNOME/pango/issues/404#note_676284
https://github.com/harfbuzz/harfbuzz/issues/1892#issuecomment-552877664
so I won't include additional screenshots.

I'm not sure what should Debian do provided upstream seems a bit dead... But
breaking font rendering in Gtk apps across all Debian installations doesn't
seem like a very good outcome either. :-(

Any ideas?

If anyone else is experiencing this, my workaround:

/etc/apt/sources.list:
deb http://snapshot.debian.org/archive/debian/20200401T000000Z/ testing main contrib non-free

/etc/apt/preferences:
Package: *pango*:*
Pin: origin "snapshot.debian.org"
Pin-Priority: 1100

-- System Information:
Debian Release: bullseye/sid
  APT prefers testing
  APT policy: (990, 'testing'), (990, 'stable'), (500, 'unstable-debug'), (500, 'testing-debug'), (500, 'stable-debug'), (500, 'unstable'), (500, 'stable'), (1, 'experimental-debug'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 5.4.0-4-amd64 (SMP w/4 CPU cores)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_USER, TAINT_WARN, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=cs_CZ.UTF-8, LC_CTYPE=cs_CZ.UTF-8 (charmap=UTF-8), LANGUAGE=cs_CZ.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages libpango-1.0-0 depends on:
ii  fontconfig    2.13.1-2+b1
ii  libc6         2.30-4
ii  libfribidi0   1.0.8-2
ii  libglib2.0-0  2.64.1-1
ii  libthai0      0.1.28-3

libpango-1.0-0 recommends no packages.

libpango-1.0-0 suggests no packages.

-- no debconf information

-- 
Tomáš Janoušek, a.k.a. Pivník, a.k.a. Liskni_si, http://work.lisk.in/